All patents, scientific articles, and other documents mentioned herein are incorporated by reference as if reproduced in full below. Cancer is the rapid and uncontrolled proliferation of new cells within a body, and is a leading cause of death in animals, including humans. This proliferation far exceeds the normal level of apoptosis, the physiological process essential to normal development and homeostasis of multicellular organisms. (Stellar, Science 267:1445-1449 (1995)).
Chemotherapy, often used in conjunction with radiation treatments and surgery, is a standard cancer treatment used today. Chemotherapy is generally understood to mean medications or drugs that destroy cancer cells. Presently, there are over one hundred drugs used in various combinations to treat cancer. (The American Cancer Society, Consumers Guide to Cancer Drugs, Jones and Bartlett Publishers, (2000)). “All these drugs have one characteristic in common. They work because they're poisons.” (Moss, Questioning Chemotherapy, Equinox Press, pg. 77, (2000)). Chemotherapeutic agents are highly toxic and typically have narrow therapeutic indices. These agents exhibit little specificity for malignant cells, and they cannot discriminate effectively between normal and malignant cells. Consequently, all cells and tissues, and especially rapidly proliferating cells, such as the bone marrow cells, the spermatogonia, and the gastrointestinal crypt epithelium cells, are very vulnerable. (Baquiran, Cancer Chemotherapy Handbook, Lippincott, pg. 85 (2001)). Moreover, the side effects of chemotherapy can be horrific, as is well known to those of skill in the art and to those unfortunate enough to have the art practiced upon them. (The American Cancer Society, Consumers Guide to Cancer Drugs, Jones and Bartlett Publishers, (2000)). See also, (Baquiran, Cancer Chemotherapy Handbook, Lippincott, p 85 (2001)); (Chu & Devita, Physicians' Cancer Chemotherapy Drug Manual, 2003, Jones and Bartlett Publishers, (2003)); (Lance Armstrong, It's Not About the Bike, Berkley Publishing, (2000)), (King, King and Pearlroth, Cancer Combat, Bantam Books, (1998)); (Rich, The Red Devil, Three Rivers Press, (1999)); and (Marchione, Hopes in cancer drug dashed, Milwaukee Journal Sentinel, May 22, (2002)). Current cancer treatments including chemotherapy do not generally work well with solid tumors. (Moss, Questioning Chemotherapy, Updated Edition, Equinox Press, 2000:18) and (Masters and Koberle, in Curing Metastatic Cancer: Lessons from Testicular Germ-Cell Tumours, Nature Reviews, 3(7) (July 2003)).
Resistance can develop to chemotherapeutic agents, causing the agents to work for some types of cancer, but not for others, or not work at all. Resistance has been demonstrated to every single chemotherapeutic agent ever developed. This resistance may be innate, acquired or emergent resistance. (Chu & Devita; Physicians' Cancer Chemotherapy Drug Manual, 2003, Jones and Bartlett Pub. (2003)). In addition, it has been commonly assumed that combining chemotherapeutic agents will result in regimens with superior response rates. However, a study demonstrated that chemotherapy agents, used either in sequence or in combination for metastatic breast cancer, provided equivalent results with regard to survival and quality of life was measured. (Sledge, et al., Phase III, Trial of Doxorubicin, paclitaxel, and the combination of doxorubicin and paclitaxel as front-line chemotherapy for metastatic breast cancer: an intergroup trial, J. of Clin. Oncology, 21 (4):588-592 (February 2003)).
Additionally, a study utilizing four of the newer chemotherapy regimens and drugs produced a two-year survival rate of 11% and substantial toxicity. The response and survival rate did not differ significantly amongst the four groups treated with the different regimens for advanced non-small-cell lung cancer. (Schiller, et al., Comparison of Four Chemotherapy Regimens for Advanced Non-Small-Cell Lung Cancer, The N. Eng. J. of Med., 346(2):92-98 (January 2002)).
Cancer cells are well known to have a higher glucose uptake and metabolism, and the resulting enhanced glycolysis can serve as an indication of a malignant transformation. (Mehvar, Dextrans for targeted and sustained delivery of therapeutic and imaging agents, J. of Controlled Release, 69:1-25 (2000)); (Essner, et al., Advances in FDG PET Probes in Surgical Oncology, Cancer Jour. 8:100-108 (2002)). Cancer cells utilize and metabolize glucose at high rates, (even in the presence of high oxygen concentrations) forming mostly lactate. (Warburg, O., On The Origin of Cancer Cells, Science 123 (3191): 309-314 (February 1956)). Lactate, therefore, is detected in cancer cells at much higher levels than in the corresponding normal tissues. (Rivenzon-Segal, et. al., Glycolysis as a metabolic marker in orthotopic breast cancer, monitored by in vivo 13C MRS, Amer. J. Phys. Endocrinology Metabolism, 283: E623-E630 (2002); See also, (Lee and Pedersen, Glucose Metabolism in Cancer, J. of Biol. Chem. 278 (42):41047-41058 (October 2003)); (Gatenby and Gawlinski, The glycolysis phenotype in carcinogenesis and tumor invasion: insights through mathematical models, Cancer Res., 63(14):3847-54 (July 2003)); (Degani, The American Society of Clinical Oncology, Intn'l J. of Cancer, 107:177-182 (November 2003)); (Warburg, O. The Prime Cause and Prevention of Cancer, Konrad Triltsch, p 6. (1969)). Glucose typically enters most cells by facilitated diffusion through one of a family of glucose transporters. (Katzung, Basic & Clinical Pharmacology, McGraw Hill Co. Inc., pg. 715 (2001)). Glucose forms that are incompatible with these transporters can be taken in by phagocytosis, also known as endocytosis, either by a cell of the phagocytic system or a cell associated with a tissue. The phagocytic system, also known as the reticuloendothelial system (“RES”), or the mononuclear phagocyte system (“MPS”), is a diffuse system, which includes the fixed macrophages of tissues, liver, spleen, lymph nodes and bone marrow, along with the fibroblastic reticular cells of hemotopoietic tissues.
Glucose initiates, promotes, drives and amplifies the growth and metastasis of tumor cells. Anaerobic glycolosis favored by tumor cells, is a very inefficient and primitive process to produce ATP, requiring prodigious amounts of glucose. Thus, the scientific community is currently working on ways to deprive tumor cells of glucose. (Van Dang et al, The Proc. of the Nat'l Acad. of Sci. 95:1511-1516 (1998)). (Pedersen, Inhibiting glycolysis and oxidative phosphorylation, 3-BrPA abolishes cell ATP production, Reuters News, (Jul. 18, 2002)). An in vivo murine study on xenograft models of human osteosarcoma and non-small cell lung cancer found that the glycolytic inhibitor 2-deoxy-D-glucose in combination with adriamycin or paxlitaxel, resulted in significant slower tumor growth. (Maschek, et al., 2-deoxy-D-glucose increases the efficacy of adriamycin and paclitaxel in human osteosarcoma and non-small cell lung cancers in vivo, Cancer Res., 64(1):31-34 (2004)). In addition, positive clinical results have been found with the anti-cachexia drug, hydrazine sulfate, which inhibits neoglucogenesis. (Moss, Cancer Therapy, Equinox Press, p 316 (1992)). Many dietary modifications directed at depriving cancer cells of glucose have also been studied. (Quillin, Beating Cancer with Nutrition, Nutrition Times Press, p 225 (1998)); (Quillin, Cancer's Sweet Tooth, Nutrition Science News, (April 2000)); and (Hauser & Hauser, Cancer-Treating Cancer with Insulin Potentiation Therapy, Beulah Land Press, (2001)).
Copper (Cu), is an essential trace element, and necessary for life in organisms ranging from bacteria to mammals. Copper promotes and is an essential co-factor for angiogenesis, a requirement for the growth of cancer, especially solid tumors. (Brewer, Handbook of Copper Pharmacology and Toxicology, Humana Press, Chap. 27, (2002)); (Brem, Angiogenesis and Cancer Control: From Concept to Therapeutic Trial, Cancer Control Jour., 6 (5):436-458 (1999). Since angiogenesis is generally not required in adults, the inhibition of angiogenesis through copper removal, copper reduction therapy, or copper withholding, has been explored as a possible mechanism for inhibiting further tumor growth. (Brewer, supra); See, also U.S. Pat. No. 6,703,050 of Brewer et al. Tumors of many types have a great need for copper and sequester copper, because copper is an essential cofactor for angiogenesis and proliferation. (Brewer, Copper Control as an Antiangiogenic Anticancer Therapy: Lessons from Treating Wilson's Disease, Exp. Bio. and Med., 226(7):665-673 (2001)). Because of this avidity for copper, and effects of copper promoting tumor initiation, growth and metastasis, the scientific community continues to develop methods and pharmaceuticals of withholding copper from tumor cells. (Brem, supra); (Brewer, supra); (Brewer, et al., Treatment of Metastatic Cancer with Tetrathiomolybdate, an Anticopper, Antiangiogenesis Agent: Phase I Study, Clin. Cancer Res., 6:1-10 (2000)); (Redman, Phase II Trial of Tetrathiomolybdate in Patients with Advanced Kidney Cancer, Clin. Cancer Res., 9:1666-1672 (2003)); (Pan, et al., Copper Deficiency Induced by Tetrathiomolybdate Suppresses Tumor Growth and Angiogenesis, Cancer Res., 62:4854-4859 (2002)); (Teknos, et al., Inhibition of the Growth of Squamous Cell Carcinoma by Tetrathiomolybdate-Induced Copper Suppression in a Murine Model, Arch. of Otolaryngology: Head And Neck Surgery, Oncolink Cancer News, Reuters, 129:781-785 (2003)); (Yoshiji, et al., The Copper Chelating Agent, trientine, suppresses tumor development and angiogenesis in the murine heptatocellular carcinoma cells, Int'l J. of Cancer, 94:768-773 (December 2001); (Yoshiji, et al., The copper chelating agent, Trientine attentuates liver enzymes-altered preneoplastic lesions in rats by angiogenesis suppression, Oncology Rep., 10(5):1369-73 (2003)); (Brem, et al., Penicillamine and Reduction of Copper for Angiosuppressive Therapy of Adults with Newly Diagnosed Glioblastoma, H. Lee Moffitt Cancer Center & Research Inst., (1999)); (Sagripanti and Kraemer, Site-specific Oxidative DNA Damage at Polyguanosines Produced by Copper Plus Hydrogen Peroxide, J. of Biol. Chem., 264(3):1729-1734 (1989)).
Copper may also promote cancer growth in ways such as damaging DNA. (Sagripanti, supra (1999)). The destructive activity of copper in a cell includes binding to DNA, cleaving DNA, in the presence of reducants and hydrogen peroxides, non-specific disruption of cellular function, and the generation of free hydroxyl radicals through Haber-Weiss reactions. (Theophanides, et al., Copper and Carcinogenesis, Critical Reviews In Oncology/Hematology, 42:57-64 (2002)). Copper also plays a role in the formation of reactive oxygen species (“ROS”). (Sagripanti, DNA Damage Mediated by Metal Ions with Special Reference to Copper and Iron, Met. Ions Biol. Syst. 36:179-209(1999)).
The use of copper has also been disclosed for the treatment of cancer in a number of U.S. Patents as well: U.S. Pat. No. 4,952,607 discloses copper complexes exhibiting super oxide dismutase-like activity in mammalian cells; U.S. Pat. No. 5,124,351 discloses the use of copper chelate of nitrilotriacetic acid or a copper chelate of bis-thiosemicarbazone; U.S. Pat. No. 5,632,982 discloses the use of copper chelates in conjunction with a surface membrane protein receptor internalizing agent, particularly TNF for use against target cells; and U.S. Pat. No. 6,706,759 discloses the use of dithiocarbamate derivatives and copper.
It is also known that a quantitative difference exists between cancer cells and normal cells with respect to iron requirements, because enhanced acquisition of iron initiates, promotes, and amplifies the growth, and metastasis, of tumor cells. Iron is an essential transition metal for a large number of biological processes ranging from oxygen transport through DNA synthesis and electron transport. Iron is also involved in carcinogenic mechanisms, which include the generation of DNA damaging reactive oxygen species, and the suppression of host cell defenses. (Desoize, B., Editor, Cancer in Metals and Metal Compounds: Part I—Carcinogenesis, Critical Reviews In Oncology/Hematology, 42:1-3 (2002)); (Galaris, et al., The Role of Oxidative Stress in Mechanisms of Metal-induced Carcinogenesis, Critical Reviews In Oncology/Hematology, 42:93-103 (2002)); (Weinberg, Cancer and Iron: a Dangerous Mix, Iron Disorders Insight, 2(2):11 (1999)); (Weinberg, The Development of Awareness of the Carcinogenic Hazard of Inhaled Iron, Oncology Res. 11:109-113 (1999)); (Weinberg, Iron Therapy and Cancer, Kidney Int'l, 55(60): S131-134 (1999)); (Weinberg, The Role of Iron in Cancer, Euro. J. Cancer Prevention, 5:19-36, (1996)); (Weinberg, Iron in Neoplastic Disease, Nutrition Cancer, 4(3):223-33 (1993)); (Stevens, et al., Body Iron Stores and the Risk of Cancer, N. Eng. J. of Med., 319(16):1047-1052 (1988)).
A number of pharmaceuticals have been developed to control and restrict the supply of iron to tumor cells using different approaches, including intracellular iron-chelating agents for withdrawal of the metal, use of gallium salts to interfere with iron uptake, and utilization of monoclonal antibodies to transferrin receptors on tumors to block the uptake of iron. For example, U.S. Pat. No. 6,589,96, incorporated herein in its entirety, teaches the use of iron chelators as chemotherapeutic agents against cancer to deprive cancer cells of iron. See also, (Kwok, et al., The Iron Metabolism of Neoplastic Cells: alterations that facilitate proliferation?, Crit. Rev. In Oncology/Hematology, 42:65-78 (2002), discloses tumor cells express high levels of the transferrin receptor 1 (TFR1) and internalize iron (Fe) from transferrin (TF) at a tremendous rate.); (Desoize, B. Editor, Cancer and Metals and Metal Compounds, Part II—Cancer Treatment, Crit. Rev. In Oncology/Hematology, 42:213-215 (2002)); (Collery, et al., Gallium in Cancer Treatment, Crit. Rev. In Oncology/Hematology, 42:283-296 (2002)); (Weinberg, Development of Clinical Methods of Iron Deprivation for Suppression of Neoplastic and Infectious Diseases, Cancer Investigation, 17(7):507-513 (1999)); (Weinberg, Human Lactoferrin: a Novel Therapeutic with Board Spectrum Potential, Pharmacy & Pharmacology, 53 (October 2001)); (Richardson, Iron Chelators as therapeutic agents for the Treatment of Cancer, Crit. Rev. In Oncology/Hematology, 42:267-281 (2002)).
When an iron dextran complex is administered to the blood system, the cellular toxicity of iron is blocked by the dextran sheath or shell in doses above or below the rate of clearance of the RES system. (Lawrence, Development and Comparison of Iron Dextran Products, J. of Pharm. Sci. & Tech., 52(5):190-197(1998)); (Cox, Structure of an iron-dextran complex, J. of Pharma & Pharmac, 24:513-517 (1972)); (Henderson & Hillman, Characteristics of Iron Dextran Utilization in Man, Blood, 34(3):357-375 (1969)); U.S. Pat. No. 5,624,668). Iron dextran can remain in the plasma and traffic throughout the body for weeks inertly, while being removed from the plasma by the phagocytic system and cancer cells.
Copper and iron are essential micronutrients for all organisms because of their function as co-factors in enzymes that catalyze redox reactions in fundamental metabolic processes. (Massaro, editor, Handbook of Copper Pharmacology and Toxicity, Humana Press, 2002, Chapter 30, p 481). Studies have shown synergistic interactions between iron and copper, which result in a significant increase in utilization of iron as compared to the utilization found with iron only compounds. (Massaro, Chap. 30, supra). To bind iron to the plasma protein transferrin, oxidation is required from Fe2+ to Fe3+. The oxidation may be mediated by multicopper ferroxidases, hephaestin or ceruloplasmin. Hephaestin may act together with Ferroportin1 at the surface of enterocytes to oxidize Fe2+ to Fe3+ prior to export into blood plasma for loading onto transferrin. An additional important role of ceruloplasmin is the mobilization of iron from tissues such as the liver where ceruloplasmin is synthesized. The ceruloplasmin can contain six copper atoms, is secreted from the liver, and can carry at least 95% of total serum copper for delivery to tissues. In addition, ceruloplasmin, via its ferroxidase activity, mediates iron release from the liver, also for delivery to tissues. Thus, both copper and iron support the hematopoietic system, especially red blood cell formation. Each is essential for the formation of red blood cells.
The American Cancer Society report, Cancer Facts and Figures 2003, discloses that “cancer is a group of diseases characterized by uncontrolled growth and spread of abnormal cells. About 1,334,100 new cancer cases are expected to be diagnosed in the United States in 2003, with 556,500 cancer deaths expected in 2003.” The present invention includes, but is not limited to, the treatment of these cancers disclosed in Cancer Facts and Figures 2003, page 4, supra, such as, Oral Cavity and Pharynx, Digestive System, Respiratory System, Bones and Joints, Soft Tissue, Skin, Breast, Genital System, Urinary System, Eye and Orbit, Brain and Other Nervous System, Endocrine System, Lymphoma, Multiple Myeloma, Leukemia, and Other Unspecified Primary Sites. Treatment with the present invention also includes basal and squamous cell skin cancers and in situ carcinomas, Hyper Proliferative Disorders, myelodysplasia disorders and Plasma Cell Dyscrasias, which is characterized by an increase in plasma cells in the bone marrow, or uncommonly, other tissue. A description of these clinical abnormalities is disclosed by Markman, M. D. in Basic Cancer Medicine, W. B. Saunders Co., p. 103, (1997).
It would be advantageous to develop an effective chemotherapeutic agent which employs biocompatible materials, materials which feed every cell in the body, to effectuate cell death, at minimum, prevent cancer cell replication, and avoid classic and numerous deadly chemotherapeutic side effects. Such a therapeutic agent would avoid the issues of tissue resistance and lack of specificity that are caused by many pharmaceuticals, thereby destroying or disabling many previously unmanageable cancers without debilitating or killing the patient.
With respect to viral diseases, Hepatitis is a prime example. Hepatitis, generally, is caused by viral infections and may include a number of different strains. Hepatitis C is the most common strain and the most blood-borne infection and one of the most important causes of chronic liver disease in the United States. Hepatitis C virus (“HCV”) is a disease causing inflammation of the liver. HCV is a single-stranded RNA virus of the family Flaviviridae and genus hepacivirus and has at least 6 major genotypes and more than 50 subtypes of HCV. Hepatitis C is the leading cause of liver transplantation in the United States as well as 15 percent of acute viral hepatitis, 60 to 70 percent of chronic hepatitis, and up to 50 percent of cirrhosis, end-stage liver disease, and liver viruses, including heptocellular carcinoma. The U.S. Center for Disease Control and Prevention reports that approximately 1.8 percent of the U.S. population, or 3.9 million Americans, have been infected with HCV, and of those, most cases are undiagnosed. Globally, the World Health Organization estimates that 170 million persons, which equates to approximately 3 percent of the world's population, are chronically infected with HCV, and additionally 3 to 4 million persons are newly infected each year.
The course of hepatitis C infection can be accelerated by the immunodeficiency associated with HIV infection, and thereby increasing the incidence of cirrhosis. Co-infection with the hepatitis B virus (“HBV”) also has been associated with increased severity of chronic hepatitis C, and accelerated progression to cirrhosis. In addition, HBV co-infection seems to enhance the risk of hepatocellular carcinoma development. (See, for example, eMedicine.Com, Inc for co-infection information).
Hepatitis A is caused by the hepatitis A virus (“HAV”), a nonenveloped, positive stranded RNA virus of the genus hepatovirus of the family Picornavirus. HAV interferes with the liver's functions while replicating in hepatocytes. As a consequence of pathological damage, the liver becomes inflamed. HAV has been found to be the major cause of infectious hepatitis.
Hepatitis B is caused by the hepatitis B virus (“HBV”), an enveloped virus containing a 42 nm partially double stranded, circular DNA genome, and classified within the family Hepadnavirus. Hepatitis B is a serious and common infectious disease of the liver, affecting millions of people throughout the world. HBV is believed to be the major cause of serum hepatitis. The hepatitis delta virus (“HDV”) was shown to rely on HBV for transmission because it used the hepatitis B surface antigen (HBsAg) as its own virion coat. The antigen resembles hepatitis B core antigen (“HbcAg”) in its subcellular localization. Its presence was always associated with HBV infection, but it rarely coexisted with HBcAg. HDV infection can be acquired either as a co-infection with HBV or as a superinfection of persons with chronic HBV infection. Persons with HBV-HDV co-infection may have more severe acute disease and a higher risk of fulminant hepatitis (2%-20%) as compared with those infected with HBV alone. However, chronic HBV infection appears to occur less frequently in persons with HBV-HDV co-infection. Chronic HBV carriers who acquire HDV superinfection usually develop chronic HDV infection. In long-term studies of chronic HBV carriers with HDV superinfection, 70%-80% have developed evidence of chronic liver diseases with cirrhosis compared with 15%-30% of patients with chronic HBV infection alone.
Hepatitis E is caused by the hepatitis E virus (“HEV”), a nonenveloped, spherical, positive-stranded RNA virus. Several different strains have been isolated, partially characterized and molecularly cloned (1990-92). Although originally classified within the family of Caliciviruses, they are now unclassified. HEV causes self-limited acute viral hepatitis in adults aged 1540. Symptomatic HEV infection is uncommon in children; although HEV infection is frequent in children, it is mostly asymptomatic and anicteric.
Vaccines exist to protect against hepatitis A and hepatitis B. Hepatitis D, caused by a defective virus, is harmless without HBV. Both hepatitis A and hepatitis E are self-limited and, in most cases, will cease after a period of time. Hepatitis C, however, is neither defective nor self-limiting, and no vaccine currently exists to prevent against infection.
Some patients with typical signs and symptoms of acute viral hepatitis do not have serologic markers of any of these types of viral hepatitis and can be classified as having non-ABCDE hepatitis. Recently, new viruses have been discovered in patients with non-ABCDE hepatitis.
Current treatment options for people with chronic hepatitis, particularly hepatitis C, usually combine lifestyle changes with a strict drug regimen. Because of the metabolizing role of the liver, diet most likely plays an important role in influencing the rate of progression of the disease. A diseased liver in a person infected with hepatitis C can particularly be affected by an excess of certain products, including sodium, fat, and especially alcohol, which lowers the effectiveness of medications. Due to the failure of many conventional treatments and the severity of the side effects associated with the drug regimens, some people infected with hepatitis C turn to alternative therapies, which can include the use of herbals and botanicals, relaxation, and spiritual healing.
Interferons are the mainstay of conventional drug therapy hepatitis C. Interferon is a naturally occurring glycoprotein that is secreted by cells in response to viral infections. Interferons bind to specific receptors on the cell surface initiating intracellular signaling via a complex cascade of protein-protein interactions leading to rapid activation of gene transcription. Interferon-stimulated genes modulate many biological effects including the inhibition of viral replication in infected cells, inhibition of cell proliferation, and immunomodulation. Various recombinant forms of interferon alpha, and interferon alpha-2b, and a recombinant non-naturally occurring type I interferon are approved to treat chronic viral hepatitis C. However, interferon is known to cause both physical and psychological side effects, such as, irritability, depression, anxiety, and suicidal behavior; decrease in the number of white blood cells and platelets; heart problems, body organ problems, which can result in autoimmune disease, including systemic lupus erythematosus. Flu-like side effects are also common. Interferon is often pegylated, by linking the polyethylene glycol (“PEG”) to the interferon molecule via a stable amide bond to lysine, as protection from immune system destruction and provide a longer residence time in the body. Ribavirin is often combined with an interferon for treatment of hepatitis and is believed to have some effect in preventing the multiplication of viruses.
Infectious diseases kill over 10 million people each year, more than 90 percent of whom are located in the developing world. Malaria, and other vector-borne diseases, infects an approximately one billion people worldwide. Those figures are now expected to increase as malaria is undergoing a resurgence based on factors such as the emergence of drug-resistant strains of the parasite, the appearance of parasite-carrying mosquitoes that are resistant to insecticides, environmental changes, and an increased population.
Most anti-infective malarial drugs interfere with aspects of protozoan metabolism that differ significantly from the human host. The Plasmodium species of the malaria parasite infect humans. P. falciparum parasites causes the most lethal form of malaria in humans and is the most common species. Other species, including P. vivax, P. ovale and P. malariae, may cause less virulent types of the disease. Mosquitoes inject the parasites, also known as sporozoites, into subcutaneous mammal tissue, or occasionally directly into the bloodstream. The parasitic sporozoites then travel to the liver, where the sporozoites are believed to pass through several hepatocytes before invasion. Parasitic development then begins. A co-receptor on the sporozoites mediates invasion. The co-receptor, thrombospondin, binds, via certain domains, specifically to heparin sulphate proteoglycans on hepatocytes in the region in apposition to sinusoidal endothelium and Kuppfer cells. Each sporozoite develops into tens of thousands of merozoites once inside the hepatocyte, which can each invade an erythrocyte (or red blood cell “RBC”) upon release from the liver. Plasmodium infects host erythrocytes during the phase of their life cycle that gives rise to the symptoms of malaria. The parasite has a 48-hour cycle of invasion, growth and release from an infected erythrocyte. During this cycle, the parasite induces a large increase in the permeability of the host red blood cell membrane, allowing the parasite to garner nutrients from the host bloodstream, and to discharge waste products. The malaria parasite degrades up to 80% of the hemoglobin in the host cell. This degradation occurs in lysosomal food vacuoles and involves, at minimum, aspartic proteases (plasmepsins), the cysteine protease falcipain 2, and many additional peptidases including a metallopeptidase. The results include a release of large amounts of Fe(II) heme, which is rapidly oxidized to Fe(III) hematin and sequestered as an inert pigment called hemozoin that comprises a structured lattice of aggregated heme dimers.
Parasite survival within its host requires several metabolic adaptations that render it susceptible to chemotherapeutic attack and some drug targets can be targeted to functions of distinct organellar structures. Quinoline, aryl alcohol antimalarial-drugs, and the artemisinins and other antimalarial peroxides are concentrated in food vacuoles and are believed to exert their activity through interaction with heme. Quinolines are believed to disrupt or prevent effective formation of haemozoin by binding to heme through an alternate stacking of their planar aromatic structures, which results in heme-mediated toxicity to the parasite, and may involve inducing lipid peroxidation. The artemisinins can undergo oxidoreductive cleavage of their peroxide bond in the food vacuole, most likely through interaction with Fe(II) heme. These interactions are believed to generate fatal free radical-induced damage to the parasite. However, the exact mechanisms of generation and mechanisms of parasite death are unknown.
However, resistance is developing many commonly distributed drugs, in particular the less expensive types. Additionally, in practice, the costs of treating malaria patients with most anti-malarial-infected drug may not be affordable for most communities or households in countries, which may already have widespread resistance to commonly available, inexpensive drugs.
It would be advantageous to develop an effective agent which employs biocompatible materials to have an anti-malarial-treatment which simultaneously kills the protozoa, supports the production of red blood cells, white blood cells, platelets, addresses the widespread iron deficiency and anemia, and supplies carbohydrates, and is composed of biological materials which are native to the body, and nourishes every normal cell.
Ebola Hemorrhagic Fever, commonly referred to as “Ebola,” is one of the most lethal viruses to infect humans and nonhuman primates. Caused by the Ebola virus, this infectious disease is named for the river in Zaire where it was first discovered in 1976. Since its discovery, different strains of the virus have caused epidemics with 50 to 90 percent mortality rates.
The Ebola virus is a member of the negative-stranded RNA virus family Filoviridae, similar to the Marburg virus, a related but less-fatal hemorrhagic disease. The particles are pleomorphic, however the basic structure is long and filamentous, essentially bacilliform and the viruses often takes on a “U” shape. The particles can be up to 14,000 nm in length and average 80 nm in diameter. The Ebola virus consists of an outer lipid membrane embedded with glycoproteins, and an inner viral capsid which surrounds the viral RNA. The viral genome consists of a single negative strand of RNA that is non-infectious itself, non-polyadenylated, with a linear arrangement of genes. The whole virion, that is, the complete viral particle consisting of RNA surrounded by a protein shell, constitutes the infective form of a virus. See, for example, the web sites of the United States Center for Disease Control (“CDC”).
The virus enters a cell via an unknown mechanism, and the virus transcribes its RNA and replicates in the cytoplasm of the infected cell. As the infection progresses, the cytoplasm of the infected cell develops “prominent inclusion bodies” that contain the viral nucleocapsid, which can become highly structured. The virus then assembles, and buds off the host cell, and obtains its lipoprotein coat from the outer membrane of the infected cell.
Four different strains of Ebola are known to exist, three of which cause disease in humans. Named for their site of outbreak, they are Ebola-Zaire (90% fatality rate), Ebola-Sudan (50% fatality rate), and Ebola-Ivory Coast (one case reported; patient survived). The fourth, Ebola-Reston, has caused disease in nonhuman primates, but not in humans. Confirmed cases of Ebola Hemorrhagic Fever have been reported in several African countries as well as, in England where a laboratory worker became ill as a result of an accidental needle-stick. The Ebola-Reston virus caused severe illness and death in monkeys imported to research facilities in the United States and Italy; several research workers became infected with the virus during these outbreaks, but did not become ill. Ebola typically appears in sporadic outbreaks, usually spread within a health-care setting through the inadequate sterilization of needles. It is likely that sporadic, isolated cases occur as well (like Ebola-Ivory Coast), but go unrecognized and unreported. The natural reservoir of the Ebola virus remains unknown.
Little is known about the pathogenesis of filoviruses. It is known, however, that Ebola attacks cells important to the function of lymphatic tissues. The virus can be found in fibroblastic reticular cells (“FRC”) among the loose connective tissue under the skin and in the FRC conduit in lymph nodes. This allows Ebola to rapidly enter the blood and leads to disruption of lymphocyte homing at high endothelial venules. See the Stanford University website on filoviruses. Due to the nature of the hemorraghic fever, little is known about the host immune response to infection. Antibodies that are produced primarily attack the surface glycoproteins of the virus. It is known that patients who die usually have not developed a significant immune response to the virus at the time of death. See. For example, the website of the United Sates Center for Disease Control. Anti-Ebola antibodies have been found in domestic guinea pigs, but there is no evidence of its transmission to humans. See, the Canadian Office of Laboratory Safety website.
Diagnosing Ebola in an individual who has been infected only a few days is difficult because early symptoms, such as red eyes and a skin rash, are nonspecific to the virus and are seen in other patients with diseases that occur much more frequently. Antigen-capture enzyme-linked immunosorbent assay (ELISA) testing, IgM ELISA, polymerase chain reaction (PCR), and virus isolation can be used to diagnose a case of Ebola HF within a few days of the onset of symptoms. Persons tested later in the course of the disease, or after recovery, can be tested for IgM and IgG antibodies. The disease can also be diagnosed retrospectively in deceased patients by using virus isolation, immunohistochemistry testing, or PCR.
No known cure for Ebola has thus far been successful. Present treatments are directed at maintaining renal function and electrolyte balance; and combating hemorrhage and shock; transfusion of convalescent serum may also be beneficial. Standard antiviral therapies, including interferon, which boosts the immune system, and ribavarin, an antiviral drug, have not been shown to be effective against the Ebola virus. See, the Canadian Office of Laboratory Safety website. The longer a patient can be kept alive, the greater the chance of recovery because more time is provided for the development of a natural immune response. To date, there are no vaccines for Ebola approved for use in humans.
Investigators at the Vaccine Research Center (VRC), in conjunction with the US Army Medical Research Institute for Infectious Diseases (USAMRIID), and the Centers for Disease Control and Prevention (CDC), have developed a potentially effective vaccine strategy for Ebola virus infection in non-human primates. In 2003, the VRC initiated the first human trial of a DNA vaccine designed to prevent Ebola infection. If this DNA vaccine, which contains three genes from the Ebola virus, proves to be safe in humans, a vaccine could be available in the future as part of a long-term preventive to protect health care workers, military personnel, and primary responders to a possible bioterrorism attack.
Smallpox is said to represent “both the zenith and nadir of human achievement”. Once the cause of the death and disfigurement of millions, it is the only disease to be successfully eradicated through a concerted and extensive effort that transcended political and ideological boundaries. Because of these efforts, no documented, naturally occurring case of this once high-mortality infection has occurred since Oct. 26, 1977. (The last naturally occurring case was an unvaccinated hospital cook in Somalia.) Smallpox was officially declared eradicated by the World Health Organization (WHO) in 1980. In spite of this, or perhaps because of this, more than two decades after its eradication, smallpox is once again a very real threat.
Officially, smallpox exists only for research purposes in two locations: the Centers for Disease Control and Prevention, Atlanta, Ga., United States and the Russian State Centre for Research on Virology and Biotechnology, Koltsovo, Novosibirsk Region, Russian Federation. The extent of clandestine stockpiles in other parts of the world remains unknown. There are concerns, however, that terrorists or rogue states may unleash the virus as one of the most devastating potential biological weapons ever conceived. As a biological weapon, smallpox could be spread in aerosol form, since smallpox is spread person to person by respiratory secretions (airborne droplets) from an infected person coughing or through direct contact with infected skin lesions.
Poxviruses, characterized by a brick-shape, are the largest animal viruses visible with a light microscope and are larger than some bacteria. Smallpox is caused by the variola virus, a member of the genus Orthopoxvirus, subfamily Chordopoxyirinae of the family Poxyiridae. Other members of the genus include cowpox, camelpox, and monkeypox. The virion contains DNA-dependant RNA polymerase; this enzyme is required because the virus replicates in the cytoplasm and does not have access to the cellular RNA polymerase located in the nucleus. Poxviruses are the only viruses known to be able to replicate in cell cytoplasm without need of a nucleus.
Two main forms of smallpox exist: variola major and variola minor. While showing similar lesions, the disease takes a much milder course in the less-common variola minor, which has a case-fatality rate of about one percent. Comparatively, variola major is fatal in approximately thirty percent of all cases. There are also two rare forms of smallpox: hemorrhagic and malignant. In the former, invariably fatal form, the rash is accompanied by hemorrhaging into the mucous membranes and the skin. Malignant smallpox is characterized by lesions that did not develop to the pustular stage, remaining soft and flat. It is also almost invariably fatal.
Viral penetration is usually attained through the respiratory tract and local lymph nodes, and is followed by the virus entering the blood (primary viremia). After penetrating the cell and uncoating, the virion DNA-dependant RNA polymerase synthesizes early mRNA, which is translated into early nonstructural proteins—mainly enzymes required for subsequent steps in viral replication. The viral DNA is replicated in typical semiconservative fashion, after which late structural proteins are synthesized that will form the progeny virions. The virions are assembled and acquire their envelopes by budding from the cell membrane as they are released from the cell. Internal organs are infected; then the virus reenters the blood (secondary viremia) and spreads to the skin. These events occur during the incubation period, when the patient is still appears well. The incubation period of smallpox can range from 7 to 17 days, and most commonly between 12 and 14 days. During this period, there is no evidence of viral shedding; the person looks and feels healthy and cannot infect others.
Existing vaccines have proven efficacy but also have a high incidence of adverse side effects; this risk is sufficiently high that vaccination is not warranted if there is no or little real risk of exposure. It is estimated that one person in every million vaccinated will die of side effects, which include eczema vaccinatum, progressive vaccinia, generalized vaccinia, and postvaccinial encephalitis. Prevention is the only effective way to deal with smallpox, for there are currently no known antiviral treatments for people infected with the virus.
Variola, prior to eradication, carried a mortality rate of 30% in unvaccinated persons. Researchers estimate that vaccinated individuals retain immunity for approximately 10 years, although the duration never has been evaluated fully. Vaccination of the general population in the United States ceased after 1980.